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The objective of this experimental investigation was to analyze the effect of various exhaust gas aftertreatment technologies on particulate number emissions (PN) of an MPFI EU5 motorcycle. Specifically, three different aftertreatment strategies were compared, including a three-way-catalyst (TWC) with LS structure as the baseline, a hybrid catalyst with a wire mesh filter, and an optimized gasoline particulate filter (GPF) with three-way catalytic coating. Experimental investigations using the standard test cycle WMTC performed on a two-wheeler chassis dynamometer, while the inhouse particulate sampling system was utilized to gather information about size-dependent filtering efficiency, storage, and combustion of nanoparticles. The particulate sampling and measuring system consist of three condensation particle counters (CPCs) calibrated to three different size classes (SPN4, SPN10, SPN23).

The proposed Euro 7 emission standard foresees that the emission behaviour of Euro 7 vehicles is monitored via an on-board monitoring (OBM) system. In Euro 7 vehicles, OBM systems will monitor the emissions of nitrogen oxides (NOX), ammonia (NH3) and particulate matter (PM) for every trip through a combination of measured and modelled data. Sensors employed to support on-board diagnostics (OBD) in current vehicles may be used to support OBM. According to the Euro 7 OBM concept presented in this paper, OBM will serve a dual purpose: the first is to warn the user of a vehicle about the need to perform repairs on the engine or the pollution control systems when these are needed. If these repairs are not performed in a timely manner, the OBM system will be able to ultimately prevent engine restart, akin to the existing low-reagent driver warning system in some compression ignition vehicles. The second purpose of OBM is to monitor the compliance of vehicle types with the emission limits.

Successful development of a product requires the consideration and balancing of many design parameters. Proposals to modify designs that have been fully implemented and put into production are often made by people who were not involved in the original design process. Such proposals, commonly focusing on a specific aspect of the product, must be evaluated in the context of the overall product and its intended use by consumers; a design change may improve performance in one area but compromise performance in another, or even introduce new problem areas. As a case in point, several proposals have been made for operator protection systems with the claim that they would reduce the frequency and severity of injuries associated with All Terrain Vehicle (ATV) operation. For example, Johnson, Carpenter, Wright & Nelson (1991) considered selected accident modes and proposed a set of design changes involving a rollover protection system (ROPS) and significant vehicle modifications.

As reported by Wright and Carpenter (1) and others, the number of accidents resulting in serious injuries and deaths associated with All Terrain Vehicle (ATV) use increased dramatically during the 1980s. It was decided that a safer, more stable ATV should be and could be built. Three-wheel and four-wheel ATVs were considered. Two three-wheel ATVs and a four-wheel ATV were modified and fabricated as prototypes. While improvements of the three-wheel ATVs were realized, there were still considerable stability problems that could not be sufficiently corrected. The four-wheel prototype, denoted as RCX 250 (roll cage experimental vehicle with a 250 cc engine), demonstrated feasibility with clear improvements in safety. Analysis of the dynamics of the RCX 250 along with the description of the features and the test results are discussed.

Injury reconstruction is a process of injury analysis which combines both medical and engineering technology to produce a composite picture of injury causation. The process is outlined and the potential applications of this analysis are detailed.

A method is proposed for simulating the effects of dimensional variation from geometric dimensioning and tolerancing (GD&T) specifications. The method converts GD&T specifications into equivalent covariance matrices which are needed in the statistical simulation of random processes. Examples are given to show how the method can be implemented.

The last few years have witnessed a steadily increasing growth in the sales and use of three and four wheel all-terrain recreational vehicles (ATVs). These vehicles are promoted for off-road use and are operated in widely varied environments ranging from dry desert surfaces to wet hilly wooded areas of the country. The design of the ATV and its intended purpose make it an attractive vehicle for a large cross-section of the general public. The general appearance of the vehicle suggests a relatively simple and safe means of transportation, even in environments which have heretofore had limited accessibility. However, it appears that the design and operational characteristics of these vehicles require more of a driver than he may initially assume as evidenced by the number of injuries and deaths that have occurred. How can the number of deaths be reduced and the severity of injuries be lessened?

In vitro biomechanical studies were conducted on fresh human cadaveric thoracolumbar spines to establish the limits of tolerance, explain the mechanism of failure, and investigate the effects of improvement in strength and stability of the injured column using Harrington distraction rods, Luque rods and modified Weiss springs. Quasistatic axial tensile loading on ligaments, compressive loads on vertebra) bodies and intervertebral discs, and flexure and compression-flexion force vectors on ligamentous columns, intact torsos and injured spines were applied to delineate the biomechanical and functional patho-anatomic characteristics. Vertical drop tests were conducted with the Hybrid II manikin to predict the forces and accelerations on the vertebral column.

The continuing development of the F-15 has included improvements to its baseline Environment Control System (ECS), an open air cycle system built around a bootstrap air cycle machine. A simple air controller schedule change and the conversion to a High Pressure Water Separator (HPMS) ECS were steps in the evolution of the F-15 ECS which yielded gains in avionics cooling capacity of about 63%. Although there was no associated capacity increase, optimization of the cooling air distribution system was done to improve avionic reliability. Recent modifications of the F-15E aircraft to accommodate the Increased Performance Engines (IPE) have included ECS changes to maintain the capacity gains achieved previously. The higher bleed pressures and temperatures characteristic of the IPE have necessitated new pressure regulators, ducts, and heat exchangers. External scoops have been added to improve ram cooling airflow.

Serious injuries are caused to the chest and thoracic organs both in front and side automobile collisions, and statistical surveys indicate that overall chest injuries are the third most frequent after head and the lower limbs. For safer design of restraint systems and vehicle interiors experimental data has to be obtained to establish chest injury criteria. Unembalmed human cadavers were used to conduct nine frontal and fourteen lateral impacts including four with a simulated arm rest. All impacts used a six inch (15.2 cm) diameter impactor with impact velocities ranging from 12 mph (19.3 kph) to 20 mph (32.2 kph). Chest impacts were also conducted on rhesus monkeys and baboons to establish primate-human injury scaling criteria. Four human volunteers were used to obtain static load deflection curves in the lateral and frontal directions. The results of the above experiments and those conducted by other investigators are presented and analyzed.

All-Terrain Vehicles, usually called ATVs, are small motorized vehicles operating on three, four, or five low-pressure, high flotation tires that are “designed” for off-road use on a variety of terrains. As the use of these ATVs increased through the 1980's, the number of accidents resulting in serious injuries and deaths associated with A N use increased dramatically. The U.S. Consumer Product Safety Commission (CPSC) along with other surveys have estimated that one out of every 25 ATVs being used will be involved in an accident requiring professional medical attention. These problems led to the federal government working out an agreement with the major manufacturers of these vehicles. One aspect of the agreement was that there would be safety and stability standards that all ATVs would have to meet to be sold in this country.

The effect of frame flexibility on the stability of constant speed, straight line motions of a motorcycle is studied by reference to linearized differential equations governing the behavior of a system of five rigid bodies, two of which are connected to each other with a hinge, a spring, and a damper, and are intended to represent a flexible frame, while the rest represent the front fork and the wheels of the vehicle. Although the configuration of the system is characterized by seven generalized coordinates, it is shown that the stability information of interest can be deduced from four first-order differential equations.

An attempt is made to describe the stability of vehicles on very rough terrain that may have large slopes. The basic premise of the paper is that the theory of ship stability is more applicable to problems of this kind than the traditional on-read vehicle stability theories. The linear theory is discussed as is driving on a rough slope, pitching, vertical oscillations and large angles. The methods of catastrophe theory as presented originally by Zeeman are used in an attempt to explain the behavior of the off-road vehicles.

Designing trucks for good ride characteristics is a challenge to the engineer, given the many design constraints imposed by requirements for transport productivity and efficiency. The objective of this lecture is to explain why trucks ride as they do, and the basic mechanisms involved. The response of primary interest is the vibration to which the driver is exposed in the cab. Whole-body vibration tolerance curves give an indication of how those vibrations are perceived at the seat; however, ride studies have shown that visual and hand/foot vibrations are also important to the perception of ride in trucks. The ride environment of the truck driver is the product of the applied excitation and the response properties of the truck. The major excitation sources are road roughness, the rotating tire/wheel assemblies, the driveline, and the engine.

The importance of fuel costs provide a strong incentive to operate the SST on existing jet fuels. Potential fuel system problems peculiar to the supersonic transport such as fuel boiling, spontaneous ignition, deposit formation, lubricity, and combustion characteristics are reviewed. The significance of these problems is established. Their severity depends on the particular environment provided by the designer. The difficulties of defining fuel properties to eliminate these problems are covered. The paper shows that major steps have been taken to operate the SST on current quality jet fuels but all necessary fuel quality control tests are not yet available.

To shape future mobility MAHLE has committed itself to foster wireless charging for electrical vehicles. The standardized wireless power transfer of 11 kW at a voltage level of 800 V significantly improves the end user experience for charging an electric vehicle without the need to handle a connector and cable anymore. Combined with automated parking and autonomous driving systems, the challenge to charge fleets without user interaction is solved. Wireless charging is based on inductive power transfer. In the ground assembly’s (GA) power transfer coil, a magnetic field is generated which induces a voltage in the vehicle assembly (VA) power transfer coil. To transfer the power from grid to battery with a high efficiency up to 92% the power transfer coils are compensated with resonant circuits. In this paper the Differential-Inductive-Positioning-System (DIPS) to align a vehicle on the GA for parking will be presented.

Since the early 1990’s, commercial vehicles have suffered from repeated vulnerability exploitations that resulted in a need for improved automotive cybersecurity. This paper outlines the strategies and challenges of implementing an automotive Zero Trust Architecture (ZTA) to secure intra-vehicle networks. Zero Trust (ZT) originated as an Information Technology (IT) principle of “never trust, always verify”; it is the concept that a network must never assume assets can be trusted regardless of their ownership or network location. This research focused on drastically improving security of the cyber-physical vehicle network, with minimal performance impact measured as timing, bandwidth, and processing power. The automotive ZTA was tested using a software-in-the-loop vehicle simulation paired with resource constrained hardware that closely emulated a production vehicle network.

Forced inversion or eversion of the foot is considered a common mechanism of ankle injury in vehicle crashes. The objective of this study was to model empirically the injury tolerance of the human ankle/subtalar joint to dynamic inversion and eversion under three different loading conditions: neutral flexion with no axial preload, neutral flexion with 2 kN axial preload, and 30° of dorsiflexion with 2 kN axial preload. 44 tests were conducted on cadaveric lower limbs, with injury occurring in 30 specimens. Common injuries included malleolar fractures, osteochondral fractures of the talus, fractures of the lateral process of the talus, and collateral ligament tears, depending on the loading configuration. The time of injury was determined either by the peak ankle moment or by a sudden drop in ankle moment that was accompanied by a burst of acoustic emission. Characteristic moment-angle curves to injury were generated for each loading configuration.